A women's advocacy group is urging the Australian government to ban minors from getting married under any circumstances.

Good Shepherd Australia New Zealand, an advocacy group for girls and women, called on the government to ensure that no minor is married in order to prevent forced marriages.

The marriage age under Australian law is 18 but court can approve a union where one of the parties is at least 16, with parental consent from both sides.

Nine Entertainment newspapers reported on Sunday that Stella Avramopoulos, chief executive of Good Shepherd, told a senate inquiry that teenagers are being forced into marriage overseas "with the expectation they will then sponsor their new spouse for migration to Australia."

"There is growing consensus internally that what is needed to end child or underage marriage is to set a minimum age of 18," she said.

The senate is hearing submissions on laws proposed by the governing Liberal National Party Coalition that would increase protections against child sexual exploitation.

The landmark act, Royal Commission into Institutional Responses to Child Sexual Abuse, which delivered its final report after five years in 2017, made 409 recommendations to address child abuse.

If passed by the parliament, the new laws would expand the definition of forced marriage to include all marriages involving children under the age of 16 regardless of consent.